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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 1 |
| 6 | 13 |
| 7 | 33 |
| 8 | 59 |
| 9 | 183 |
| 10 | 775 |
| 11 | 3549 |
| 12 | 21203 |
| 13 | 124205 |
| 14 | 885931 |
| 15 | 6938155 |
| 16 | 65072235 |
| 17 | 697161911 |
| 18 | 8870657391 |
| 19 | 129325569203 |
| 20 | 2224950934319 |
| 21 | 42682217569275 |
| 22 | 961782024725197 |
| 23 | 24665663177266467 |
[1,1,1,1,1,13,33,59,183,775,3549,21203,124205, 885931,6938155,65072235,697161911,8870657391, 129325569203,2224950934319,42682217569275, 961782024725197,24665663177266467] |